Sensitive Detection of Umami Substances in Meat with Synthesized Electrochemical Sensor Enhanced by MXene Surface-Doped Peroxidase-Mimic Nanoenzymes (Fe3O4)

Abstract

Electrochemical analysis is a powerful analytical technique with extensive applications in the food industry, offers high advantages due to its high sensitivity, low operating cost, and high-speed analysis. In this study, a novel nanoenzymes high-catalytic platform based on a conductive polymer (MXene) was established for the detection of Guanosine 5′-monophosphate (GMP). The MXene/Fe₃O₄/β-CD nanocomposites were synthesized using a self-assembly method, exhibiting significant catalytic activity and a large specific surface area. The surface morphology, functional groups and chemical bonds of MXene/Fe₃O₄/β-CD were analyzed via scanning electron microscopy (SEM), Fourier Transform Infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS). Electrochemical experiments indicated a significant amplification of GMP electrical signals on the nanoenzymatic platform. The oxidation of GMP to 8-oxo-GMP involved the transfer of two electrons (−2e⁻) and two protons (-2H⁺) at the MXene/Fe₃O₄/β-CD modified glassy carbon electrode. Under optimized conditions, this electrochemical nanoenzymatic platform achieved a low detection limit of 0.0126 μM for GMP, with linear ranges from 0.05 μM to 600 μM. The sensor demonstrated excellent selectivity and stability and was successfully applied for GMP determination in chicken, fish, pork and beef samples. This study provided a new pathway for the development of sensors for GMP detection.

Graphical Abstract